When Waitaha Move Out, Yellow-Eyed Penguins Move In

Yellow-eyed penguins roam Enderby Island, in the Auckland Islands of New Zealand. Photo credit: Wikimedia Commons / Twiddleblat

New Zealand’s University of Otago has documented one of the fastest biological transition events, where one species – the yellow-eyed penguin – replaces another – the waitaha penguin – after extinction.

This remarkable fast change took only a few decades.

Previous studies noted that the waitaha – a species that lived in New Zealand when Polynesian settlers arrived – was driven to extinction by hunting and habitat changes, before the yellow-eyed penguins moved in.

“Until now,” study leader Dr. Nic Rawlence said in a statement, “we really had no idea when one species went extinct and the other colonized.”

Researchers used carbon dating techniques and DNA testing to nail down the exact timeline of transition.

1500 AD (around 200 years after Polynesian settlement) – The waitaha penguin and flightless moa went extinct.

Early 1500s – Yellow-eyed penguins replace the waitaha.

And its no surprise humans played a heavy hand here. “This very rapid biological shift implies a substantial change in human pressure around this time,” University of Otago Associate Professor Ian Smith said. “Interestingly recent archaeological studies similarly suggest that the Maori population in southern New Zealand declined around 1500 AD, and coincided with a major dietary shift.”

The yellow-eyed penguins, it seems, were able to take advantage of the human population’s movement to establish themselves in New Zealand. But today, they are one of the rarest penguins in the world and are listed as endangered. There are fewer than 7,000 remaining today.

“This unique combination of factors seems to have allowed yellow-eyed penguins to establish the mainland populations we see today,” said the team’s project leader Professor Jon Waters.

Learn more from out source, Discovery News.